Electrical protective apparatus.



c. 8. PRICE. ELECTRICAL PROTECTIVE APPARATUS.

APPLICATION FILED NOV- l3| l9l6- 1,251,572, Patented Jan. 1, 1918.

insulating material, usually UNITED STATES PATENT OFFICE.

CHARLES S. PRICE, OF RUTHERFORD, NEW JERSEY, ASSIGNOR TO WESTERNELECTRIC COMPA NY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OFNEW YORK.

ELECTRICAL PROTECTIVE AIETARATUS.

To all whom. it may concern:

Be it known that I, CHARLES S. PRICE, a citizen of the United States,residing at Rutherford, in the county of Bergen and State of New Jersey,have invented certain new and useful Improvements in ElectricalProtective Apparatus, of which the followingis a full, clear, concise,and exactde scription.

This invention relates to devices for protee-ting circuits from abnormalvoltages, lightning and similar disturbances, and more particularly toprotective devices for circuits of low normal operating voltage. Thetype of protective device most commonly used for the protection ofcircuits of low normal operating voltages, such as telephone, telegraphand signal circuits, consists essentially of two electrodes spaced apartby a separator of mica or celluloid, To insure satisfactory operation,it is necessary that the thickness of this separator be held withinclose limits, which is difficult in the case of mica, and the use ofcelluloid or a carbonaceous material is objectionable in that afterdischarge a bridge of conducting material frequently connects the twoelectrodes.

through which the The object of this invention is to provide aprotective device not having the defects of rough usage in service, andwhich may readily be adapted to various types of mountings.

To accomplish these objects, the invention provides a cartridge type ofconstruction so arranged as to make it possible in manufacture to holdthe separation between electrodes very close to a specified amountwithout incurring the expense resulting from holding the individualparts to close manufacturing limits. Moreover, the air gaps are passesare inclosed, precluding the possibility of danger from particles ofdust bridging these gaps, and i111: inclnsin tube protects the partsfrom Specification of Letters Patent.

Patented Jan. 1, 1918.

Serial No. 131,045.

displacement or mechanical injury due to shipment or to rough handlingin service.

The several features of my invention may be more readily understoodbyreferenceto the accompanying drawings in which Figure 1 is a sectionalview of a preferred type of lightning arrester arranged for theprotection of both wires of a metallic circuit; and Fig. 2 shows asimilar arrester in one half of which the various parts are spread outto illustrate the manner in which they are assembled.

Within the tube 1 of insulating material is located a ground electrodeor plug 2 of conducting material, which is held securely in place bymeans of the screw 3, this screw also providing electrical connectionbetween the electrode and the metallic band 4 on the outsideofthetube.Removable electrodes 5, having reduced portions 6, are first assembledin conjunction with insulating bushings '7 and the ends are groundflush. The bushings are then removed and annular spacers orseparators'13 of the same thickness as the air gap desired are slippedover-the reduced portions. After replacing the bushings on the reducedportions, the electrodes are introduced into the tube 1, and are held inplace by means of located in recessed portions 9 of the electrodes, andbearing against the end caps 10, which may be fastened-to the tube bymeans of screws 11 or by any of the other methods well-known to the art,such for example, as by pinning, or by using screw caps which arethreaded directly on to the tube'. The insulating bushings 7 preferablyare"provided with recessed portions 12, thereby enlarging the arcingchamber and increasing the leakage path between the electrodes.

The finished cartridge is adapted for mounting in the common type offuse clips, the clips COIltaCtiHg with the end caps being, in practice,usually connected to the line wires to be protected, and the clipcontacting with the metal band 4: being connected to ground.

It will be noted that in this construction, accurate spacing of theelectrodes does not depend upon refinement in manufacture,'but that thespacing means is of sheet stock which can be readily and cheaplyobtained compression springs 8,

to close limits. This separator is removed from the place where arcingoccurs, and if desired, may be of a carbonaceous material, althoughordinarily a metallic separator is to be preferred What is claimed is: 4

'1. In a protective device, a tubular container, a fixed electrodetherein. a removable electrode having a reduced portion adapted tocooperate with said fixed electrode, a spacing means surrounding saidreduced portion, and resilient means for holding said removableelectrode in position.

2. In a protective device, a fixed electrode, a removable electrodehaving a reduced portion, an insulating bushing of the same length asand surrounding said reduced portion, and a separator placed between theend of said bushing and the unreduced portion of said removableelectrode.

3. In a protective device, a fixed electrode.

a removable electrode having a reduced portion, an insulating bushing ofthe same length as and surrounding said reduced portion, and a metalseparator placed between the end of said bushing and the unreducedportion of said removable electrode.

4. In a protective device, a fixed electrode, a plurality of removableelectrodes having reduced portions, insulating bushings of the samelength as and surrounding said reduced portions, and separators placedbetween the ends of said bushings and the unreduced portions of saidremovable electrodes.

5. In a. protective device, a tubular container of insulating material,metal caps inclosing the ends of said container, a fixed electrodecentrally located within said container, a pair of removable electrodeseach CHARLES S. PRICE.

